FAQs

Please follow the protocols included in the respective cell manual. To learn more about best practices for primary cell culture, click here.

“Normal” means that the cells in question were freshly isolated from non-tumour tissue. They have a finite life span in vitro. They have neither been genetically modified nor treated and/or selected to produce a continous cell line. “Normal” cells are primary cells that have been subcultured at least once.

A population doubling (PD) is a two-fold increase in the total number of cells during in vitro-culture. Calculating the number of PDs a culture has performed at a certain point gives an accurate measure of its age. In contrast, the term passage merely refers to the subculturing process, i.e. the detachment of the cells from a culture vessel (using eg. trypsin/EDTA or accutase) and replating them at a lower density to allow for further cell growth. The term passage does not take into account the different split ratios that can be applied. Different split ratios produce cultures with an identical number of passages but a varying number of doublings. Passage is therefore only a rough estimate of the actual age of a culture.

A population doubling (PD) is a two-fold increase in the total number of cells during in vitro-culture. Calculating the number of PDs a culture has performed at a certain point gives an accurate measure of its age. In contrast, the term passage merely refers to the subculturing process, i.e. the detachment of the cells from a culture vessel (using eg. trypsin/EDTA or accutase) and replating them at a lower density to allow for further cell growth. The term passage does not take into account the different split ratios that can be applied. Different split ratios produce cultures with an identical number of passages but a varying number of doublings. Passage is therefore only a rough estimate of the actual age of a culture.

“Normal” means that the cells in question were freshly isolated from non-tumour tissue. They have a finite life span in vitro. They have neither been genetically modified nor treated and/or selected to produce a continous cell line. “Normal” cells are primary cells that have been subcultured at least once.